Bus bar unit and brushless motor

Abstract

The bus bar unit (4) includes a bus bar (50) having a substantially arc-shaped substrate portion (51) and a non-conductive holder (40) covering the substrate portion (51). The holder (40) has an exposed portion (44) that exposes a part (52) of the substrate portion (51) and a guiding portion (43) that guides the bending of a lead wire (Ws) connected to the part (52) toward the exposed portion (44). Alternatively, the bus bar unit (4) may include a bus bar (50) having a plate-shaped substrate portion (51) and a resin holder (40) covering the substrate portion (51). The holder (40) may have an exposed portion (44) that exposes only a part (52) of the substrate portion (51) in a first direction (Da2) and a guiding portion (43) that guides a lead wire (Ws) joined to the part (52) from a second direction (Da1) to the first direction (Da2).

Description

Technical Field

[0001] The present invention relates to a bus bar unit and a brushless motor including the bus bar unit.

Background Art

[0002] Conventionally, in a motor, a conducting wire forming a coil built therein is known to be joined to a conductive bus bar by soldering (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in a motor including a stator as disclosed in Patent Document 1, soldering for joining a conducting wire to a bus bar may be performed manually, so there is room for improvement in that the man-hours related to the joining increase. Note that the above problems are problems that can occur when joining a conducting wire to a bus bar, and this is not limited to the case where the conducting wire is the conducting wire (winding) of a coil, nor is it limited to the case where the device provided with the bus bar is a motor or a stator.

[0005] The present invention has been devised in view of such problems, and one of its objects is to provide a bus bar unit and a brushless motor capable of reducing the man-hours related to joining a conducting wire to a bus bar. Note that this is not the only object, and another object of the present invention is to achieve an operational effect that cannot be obtained by the conventional technology, which is an operational effect derived from each configuration shown in the embodiments for carrying out the invention described later.

Means for Solving the Problems

[0006] The disclosed bus bar unit and brushless motor can be realized as the aspects (application examples) disclosed below, and solve at least some of the above problems. Note that aspect 2 is an aspect that can be additionally and appropriately selected for the bus bar unit of aspect 1 and is an aspect that can be omitted. That is, aspect First does not disclose aspects or configurations that are essential for the bus bar unit of the present case. 2 First

[0008] Aspect 1 . The disclosed First bus bar unit includes a conductive bus bar having a plate-shaped substrate portion, and a resin holder that covers the substrate portion. The holder has an exposed portion that exposes only a part of the substrate portion in a first direction in the plate thickness direction of the substrate portion, and a guide portion that is attached to the exposed portion and guides a conducting wire joined to the part from a second direction opposite to the first direction toward the first direction. A part of the above is provided at a position excluding both ends in the extending direction of the substrate portion, and portions adjacent to both sides in the extending direction of the part in the substrate portion are covered by the holder without being exposed.

[0009] Aspect 2 . In an aspect including the above aspect 1 , the bus bar unit is applied to an inner rotor type brushless motor including an annular stator and a rotor located on the inner side in the radial direction of the stator. The conducting wire is a starting wire of a winding forming a coil of the stator, and is preferably drawn out to a predetermined axial direction side in the axial direction of the stator. Further, in a state where the first direction is along the predetermined axial direction, the holder is placed on the predetermined axial direction side of the stator, the guide portion is a through hole that penetrates in the axial direction and through which the starting wire is inserted, and the exposed portion is preferably a notch that exposes the part of the substrate portion in the predetermined axial direction on the inner side or the outer side in the radial direction of the through hole.

[0010] Aspect 3 . The disclosed First brushless motor is the above aspect 2A bus bar unit including the same, the stator on which the bus bar unit is placed, and the rotor that rotates integrally with the shaft on the inner side of the stator. Aspect 4. The second bus bar unit disclosed is applicable to an inner rotor type brushless motor including an annular stator and a rotor located on the inner side in the radial direction of the stator, and includes a conductive bus bar having a plate-shaped substrate portion and a resin holder covering the substrate portion. The holder has an exposed portion that exposes only a part of the substrate portion in a first direction in the plate thickness direction of the substrate portion, and a guide portion attached to the exposed portion and guiding a conducting wire joined to the part from a second direction opposite to the first direction toward the first direction. The conducting wire is a starting wire of a winding forming the coil of the stator, is drawn out to a predetermined axial direction side in the axial direction of the stator, and with the first direction along the predetermined axial direction, the holder is placed on the predetermined axial direction side of the stator, the guide portion is a through hole through which the starting wire is inserted in the axial direction, the exposed portion is a notch exposing the part of the substrate portion in the predetermined axial direction on the inner side or the outer side in the radial direction of the through hole, and the notch is provided on the inner side of the through hole. Aspect 5. The second brushless motor disclosed includes a bus bar unit including the above Aspect 4, the stator on which the bus bar unit is placed, and the rotor that rotates integrally with the shaft on the inner side of the stator. Aspect 6. The third brushless motor of the disclosure is an inner rotor type brushless motor, comprising a busbar unit, an annular stator on which the busbar unit is placed, and a rotor located on the inner side in the radial direction of the stator and rotating integrally with the shaft on the inner side of the stator. The busbar unit includes a conductive busbar having a plate-shaped substrate portion, and a resin holder covering the substrate portion. The holder has an exposed portion that exposes only a part of the substrate portion in a first direction in the plate thickness direction of the substrate portion, and a guide portion attached to the exposed portion and guiding a conducting wire joined to the part from a second direction opposite to the first direction toward the first direction. The conducting wire is a starting wire of a winding forming a coil of the stator, is drawn out to a predetermined axial direction side in the axial direction of the stator, and with the first direction along the predetermined axial direction, the holder is placed on the predetermined axial direction side of the stator, the guide portion is a through hole penetrating in the axial direction through which the starting wire is inserted, and the exposed portion is a notch exposing the part of the substrate portion in the predetermined axial direction on the inner side or the outer side in the radial direction of the through hole. Three-phase coils are provided in the stator, the busbar is a terminal that connects different two-phase coils among the three-phase coils and is electrically connected to an external power supply device, and a plurality of the busbars are provided. The holder has the same number of through holes and notches as the busbars, and the starting wires of the windings forming each of the different two-phase coils connected by each busbar are drawn out in the predetermined axial direction from the same slot, inserted into a common through hole, and joined to the part of the busbar.

Advantages of the Invention

[0011] According to the disclosed bus bar unit and brushless motor, the man-hours related to the joining of the conducting wire to the bus bar can be reduced.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Modes for Carrying Out the Invention

[0013] With reference to the drawings, a bus bar unit and a brushless motor as embodiments will be described. The embodiments shown below are merely examples, and there is no intention to exclude various modifications and applications of technologies not explicitly shown in the following embodiments. Each configuration of the present embodiment can be implemented with various modifications without departing from the spirit thereof.

[0014] The bus bar unit includes a bus bar having a substantially arc-shaped substrate portion and a non-conductive holder that covers the substrate portion. The holder is provided with an exposed portion that exposes a part of the substrate portion and a guide portion that guides the bending of the exposed portion of the conducting wire joined to this part.

[0015] Alternatively, the bus bar unit includes a conductive bus bar having a plate-shaped substrate portion and a resin holder that covers the substrate portion. The holder is provided with an exposed portion that exposes only a part of the substrate portion in one direction (the first direction) in the thickness direction of the substrate portion and a guide portion that guides the conducting wire joined to this part. The guide portion is attached to the exposed portion and guides the conducting wire from the second direction (the other direction in the thickness direction), which is opposite to the first direction, toward the first direction.

[0016] With the above configuration, the conducting wire guided by the guide portion can be brought into contact with a part of the substrate portion and joined to the bus bar by spot welding, contributing to a reduction in man-hours. The bus bar unit described in detail below is, as an example, applied to a brushless motor. However, the application target of the above bus bar unit is not limited to motors, and may be various electrical components such as, for example, switchboards, storage batteries, and generators.

[0017] [1. Configuration] [1-1. Overall Configuration] FIG. 1 is an exploded perspective view of a brushless motor 1 (hereinafter also referred to as "motor 1") to which the bus bar unit according to the present embodiment is applied. The brushless motor 1 according to the present embodiment is an inner rotor type brushless motor, and as shown in FIG. 1, includes a rotor 2 that rotates integrally with a shaft 1s, a stator 3, and bus bar units 4 and 5. The motor 1 is configured by incorporating the rotor 2, the stator 3, and the bus bar units 4 and 5 in a bottomed cylindrical housing 6. An end bell 7 as a lid member may be combined with the opening side (left side in the figure) of the housing 6.

[0018] Hereinafter, the extending direction of the shaft 1s (the direction of the axis C of the shaft 1s) is referred to as the axial direction. Among the axial directions, the direction in which the bottom of the housing 6 is located with respect to the opening of the housing 6 (the right side in the figure of FIG. 1) is referred to as the first axial direction Da1, and the direction opposite to the first axial direction Da1 is referred to as the second axial direction Da2 (predetermined axial direction). The direction orthogonal to the axial direction and away from the axis C and the direction toward the axis C are referred to as the radial direction. Among the radial directions, the direction away from the axis C is referred to as the outer radial direction (outward), and the direction toward the axis C is referred to as the inner radial direction (inward). The direction orthogonal to the axial direction and circulating around the axis C is referred to as the circumferential direction. Among the circumferential directions, when viewed from the first axial direction Da1 side, the clockwise direction is referred to as the first circumferential direction Dc1, and the direction opposite to the first circumferential direction Dc1 (counterclockwise direction) is referred to as the second circumferential direction Dc2.

[0019] The motor 1 exemplified here includes, as shown in FIG. 1, two bus bar units 4 and 5 provided so as to sandwich the stator 3 in the axial direction. Hereinafter, the bus bar unit 4 located on the first axial direction Da1 side of the stator 3 is referred to as the first bus bar unit 4, and the bus bar unit 5 located on the second axial direction Da2 side of the stator 3 is referred to as the second bus bar unit 5. The first bus bar unit 4, the stator 3, and the second bus bar unit 5 are arranged in this order from the first axial direction Da1 toward the second axial direction Da2 and are incorporated in the housing 6. The rotor 2 and the shaft 1s are inserted inside the stator 3 and the two bus bar units 4 and 5 in the radial direction. The bus bar unit according to the present embodiment is provided (applied) as the second bus bar unit 5.

[0020] [1-2. Rotor] The rotor 2 includes, for example, a rotor core that rotates integrally with the shaft 1s, and a plurality of magnets embedded in the rotor core. The shaft 1s is a rotating shaft that supports the rotor 2 and also functions as an output shaft for taking out the output (mechanical energy) of the motor 1 to the outside. The shaft 1s is rotatably supported by the bottom of the housing 6 and the end bell 7 via two bearings 8 that sandwich the rotor core in the axial direction, for example.

[0021] [1-3. Stator] The stator 3 is an annular component having a space in which the rotor 2 is disposed on the radially inner side, and is concentrically arranged with the axis C. For this reason, each of the axial direction, radial direction, and circumferential direction of the above-described axis C is also equivalently referred to as the axial direction, radial direction, and circumferential direction of the stator 3. The stator 3 of the present embodiment has an annular (cylindrical) outer appearance shape, but the shape of the stator 3 is not limited to this.

[0022] As shown in FIG. 2, the stator 3 includes a substantially cylindrical core unit 11 and a plurality of coils 16. The core unit 11 is provided, for example, as an insert molded product obtained by molding a stator core with a resin serving as an insulator, and is fixed in the housing 6. The core unit 11 has a cylindrical outer peripheral wall 12, a plurality of teeth 13 protruding radially inward from the inner peripheral surface of the outer peripheral wall 12, and an arc-shaped inner peripheral wall 14 extending in the circumferential direction on the radially inner side of each tooth 13. The plurality of teeth 13 are spaced apart from each other at equal intervals in the circumferential direction. Between the plurality of teeth 13, the same number of slots 15 as the teeth 13 are formed. The coil 16 is formed by winding a winding wire W around each of the plurality of teeth 13, and the same number as the teeth 13 are provided.

[0023] In the stator 3 of the present embodiment, as shown in FIGS. 2 and 3, twelve teeth 13, twelve slots 15, and twelve coils 16 are provided respectively. Among the twelve coils 16 in the stator 3, four U-phase coils 16u, four V-phase coils 16v, and four W-phase coils 16w are provided respectively. A U-phase current is supplied to the U-phase coil 16u, a V-phase current is supplied to the V-phase coil 16v, and a W-phase current is supplied to the W-phase coil 16w.

[0024] In FIG. 2, only two adjacent teeth 13 out of the twelve teeth 13 are shown by broken lines in the circumferential direction. Also, among the twelve slots 15, only one slot 15 formed between the two illustrated teeth 13 is labeled. In FIG. 3, only some of the twelve teeth 13 and some of the twelve slots 15 are labeled respectively.

[0025] In the stator 3, for example, as shown in FIG. 2, two sets of U-phase coils 16u, V-phase coils 16v, and W-phase coils 16w are arranged side by side in the circumferential direction. That is, two of the four U-phase coils 16u are provided adjacent to each other in the circumferential direction, and two V-phase coils 16v are provided adjacent to each other in the circumferential direction on the second circumferential direction Dc2 side of the two U-phase coils 16u. Also, two W-phase coils 16w are provided adjacent to each other in the circumferential direction on the second circumferential direction Dc2 side of the two V-phase coils 16v, and the remaining two U-phase coils 16u out of the four U-phase coils 16u are provided adjacent to each other in the circumferential direction on the second circumferential direction Dc2 side of the two W-phase coils 16w. The remaining two V-phase coils 16v are provided adjacent to each other in the circumferential direction on the second circumferential direction Dc2 side of the remaining two U-phase coils 16u, and the remaining two W-phase coils 16w are provided adjacent to each other in the circumferential direction on the second circumferential direction Dc2 side of these.

[0026] Hereinafter, two adjacent coils 16 of the same phase are collectively referred to as a coil group 17. The stator 3 having twelve coils 16 can also be said to have two each of the U-phase coil group 17u, the V-phase coil group 17v, and the W-phase coil group 17w. Also, regarding the arrangement of the coils 16 described above, it can also be said that in the stator 3, the U-phase coil group 17u, the V-phase coil group 17v, and the W-phase coil group 17w are provided side by side in the circumferential direction in this order, and the two coil groups 17 of each phase are provided so as to face each other with the axis C interposed therebetween.

[0027] In the present embodiment, as shown in FIG. 3, each coil group 17 is formed by a single continuous winding W. That is, six windings W are provided in the stator 3, and each winding W is wound around two adjacent teeth 13 in the circumferential direction, thereby forming each coil group 17. More specifically, the winding W forming each coil group 17 is wound around one of two adjacent teeth 13 in the circumferential direction and then, without being cut, is wound around the other of the two teeth 13. The winding W forming each coil group 17 may be arranged (wired) such that the winding direction with respect to one tooth 13 and the winding direction with respect to the other tooth 13 are opposite, as shown in the drawing.

[0028] One of the start line Ws and the end line Wf of each winding W is drawn out to the first axial direction Da1 side, and the other is drawn out to the second axial direction Da2 side. In the present embodiment, as shown in FIG. 3, the start lines Ws of all six windings W are drawn out to the second axial direction Da2 side, and the end lines Wf of all six windings W are drawn out to the first axial direction Da1 side. The six start lines Ws drawn out to the second axial direction Da2 side are joined (connected) to a bus bar 50, which will be described later, of the second bus bar unit 5, and the six end lines Wf drawn out to the first axial direction Da1 side are joined (connected) to a bus bar 30, which will be described later, of the first bus bar unit 4.

[0029] Of the six starting lines Ws drawn out toward the second axis direction Da2 side, the starting lines Ws of the windings W forming the adjacent coil groups 17 may be drawn out from the same (common) slot 15. In the present embodiment, two starting lines Ws are drawn out from each of the three slots 15 that are positioned every other one in the circumferential direction. Similarly, of the six ending lines Wf drawn out toward the first axis direction Da1 side, the ending lines Wf of the windings W forming the adjacent coil groups 17 may be drawn out from the same slot 15. In the present embodiment, two ending lines Wf are drawn out from each of the three slots 15 that are positioned every other one in the circumferential direction. The starting line Ws and the ending line Wf of each winding W may be drawn out from different slots 15 or the same slot 15 as shown in FIG. 3.

[0030] Here, the starting line Ws means the portion where the winding of the winding W (conductive wire) forming each coil group 17 starts, and the ending line Wf means the portion where the winding of the winding W (conductive wire) forming each coil group 17 ends. The electricity supplied to each coil group 17 can flow from the starting line Ws toward the ending line Wf or from the ending line Wf toward the starting line Ws. For this reason, the starting line Ws and the ending line Wf are defined regardless of the flow direction of the electricity supplied to each coil group 17.

[0031] FIG. 4 is a perspective view showing a part of the core unit 11 as an example for explaining the characteristics of the starting line Ws and the ending line Wf of the winding W, and the winding W wound around the part. In FIG. 4, as a part of the core unit 11, the core unit 11 is divided into twelve in the circumferential direction, and only one of the twelve divided cores 11n is illustrated. The core unit 11 may be configured by combining a plurality of divided cores 11n that are equally spaced in the circumferential direction in this way.

[0032] Also, as described above, in the stator 3 of the present embodiment, it has been described that one winding W is wound continuously around two adjacent teeth 13 to form one coil group 17 composed of two in-phase coils 16. However, in FIG. 4, a case is illustrated in which one winding W is wound only around one split core 11n (one tooth) to form one coil 16. The stator 3 may be provided with the same number of windings W as the number of teeth 13 in this way.

[0033] As shown in FIG. 4, the start wire Ws of the winding W is constrained and fixed by the connection wire Wc because the connection wire Wc connecting the start wire Ws and the end wire Wf is wound around the tooth. Since the start wire Ws of the winding W forming each coil group 17 is fixed in this way, it has the characteristic that the radial position of the start wire Ws hardly varies (has little play) for each coil group 17. On the other hand, the end wire Wf, which is the end portion of the winding of the winding W, has the characteristic of being flexible, such as being drawn out toward the first axial direction Da1 side and the radially inner side, or being drawn out toward the first axial direction Da1 side and the radially outer side. From these characteristics, the start wire Ws is also referred to as the fixed end of the winding W, and the end wire Wf is also referred to as the free end of the winding W.

[0034] [1-4. First bus bar unit] The first bus bar unit 4 is placed on the first axial direction Da1 side of the stator 3 and is a component that connects the three-phase coils 16 for each phase. As shown in FIG. 5, it has a resin holder 20 and a plurality of bus bars 30. Each bus bar 30 is a conductive member that connects the three-phase coils 16 for each phase, extends along the circumferential direction, and is covered (embedded) in the holder 20. That is, the first bus bar unit 4 is provided such that a plurality of bus bars 30 are assembled with the resin holder 20 or are insert-molded products molded by the resin holder 20. Note that "extends along" as used in the present embodiment is not limited to extending in a direction that coincides (is parallel) with the reference direction (for example, the circumferential direction), but also includes extending in a direction inclined with respect to the reference direction.

[0035] In this embodiment, the end wires Wf of the two U-phase coil groups 17u, the end wires Wf of the two V-phase coil groups 17v, and the end wires Wf of the two W-phase coil groups 17w are drawn out toward the first axial direction Da1 side. For this reason, as shown in FIGS. 3 and 5, the first busbar unit 4 is provided with three busbars 30, namely, a U-phase busbar 30u that connects the end wires Wf of the two U-phase coil groups 17u, a V-phase busbar 30v that connects the end wires Wf of the two V-phase coil groups 17v, and a W-phase busbar 30w that connects the end wires Wf of the two W-phase coil groups 17w.

[0036] The three busbars 30 are provided, for example, as shown in FIG. 5, at the same axial position with respect to the holder 20, that is, on the same plane, without overlapping each other when viewed from the axial direction. The three busbars 30 may all have the same shape. Each busbar 30 may be provided such that a first portion 31 on the first circumferential direction Dc1 side is located radially inward of a second portion 32 on the second circumferential direction Dc2 side. The three busbars 30 are, for example, formed in a long plate shape extending spirally in the circumferential direction and are provided to be rotationally symmetric three times about the axis C. As shown in FIG. 3, each of the first portion 31 and the second portion 32 of each busbar 30 is provided so as to overlap axially with the slots 15 from which the end wires Wf of the two coil groups 17 of the phase to which the busbar 30 is connected are drawn out, and is joined to each of these end wires Wf.

[0037] The first portion 31 of each busbar 30 and the second portion 32 of any other busbar 30 than the busbar 30 may be provided so as to overlap each other when viewed from the radial direction. In other words, the first portion 31 of each busbar 30 (for example, the U-phase busbar 30u) may be provided so as to overlap, when viewed from the radial direction, with the second portion 32 of another busbar 30 (for example, the V-phase busbar 30v) that connects a coil group 17 (for example, the V-phase coil group 17v) of a phase different from the coil group 17 (for example, the U-phase coil group 17u) of the phase to which the busbar 30 is connected.

[0038] The end wires Wf of coil groups 17 of different phases drawn from the same slot 15 (for example, the end wire Wf of the U-phase coil group 17u and the end wire Wf of the V-phase coil group 17v) are each drawn (hooked) to the radially inner side and the radially outer side, respectively, before the first busbar unit 4 is placed on the stator 3. Since the portions of the winding W forming each coil group 17 drawn to the first axial direction Da1 side are all end wires Wf that become free ends as described above, such hooking of the winding W can be easily performed. Note that FIG. 5 shows a state in which the end wire Wf is drawn to the radially inner side and the radially outer side, respectively.

[0039] After the first busbar unit 4 is placed on the stator 3, the end wire Wf drawn to the radially inner side among the end wires Wf drawn from the same slot 15 (for example, the end wire Wf of the U-phase coil group 17u) is folded toward the first axial direction Da1 and the radially outer side. Thereafter, the end wire Wf (for example, the end wire Wf of the U-phase coil group 17u) is joined to the first portion 31 of the busbar 30 (for example, the U-phase busbar 30u) provided so that the slot 15 from which this end wire Wf is drawn overlaps with the first portion 31 by spot welding or soldering from the first axial direction Da1 side.

[0040] Conversely, the end wire Wf drawn to the radially outer side among the end wires Wf drawn from the same slot 15 (for example, the end wire Wf of the V-phase coil group 17v) is folded toward the first axial direction Da1 and the radially inner side after the first busbar unit 4 is placed on the stator 3. Thereafter, the end wire Wf is joined to the second portion 32 of the busbar 30 (for example, the V-phase busbar 30v) provided so that the slot 15 from which this end wire Wf is drawn overlaps with the second portion 32 by spot welding or soldering from the first axial direction Da1 side.

[0041] Thereby, the end wires Wf of different phases drawn from the common slot 15 can be joined to the busbar 30 without crossing each other. Therefore, contact (energization) prevention between the end wires Wf can be achieved, and the joining process of the end wire Wf to the busbar 30 can be easily performed.

[0042] As described above, the holder 20 is a resin member that covers the bus bar 30 and is placed on the stator 3. In the present embodiment, the holder 20 has an annular shape. The holder 20 has a main body portion 21 that forms an annular shape (doughnut shape) when viewed from the axial direction and a flat plate shape when viewed from the radial direction. The three bus bars 30 are covered by the main body portion 21. Note that, as shown in FIG. 5, three notches for exposing a part of the first portion 31 of the three bus bars 30 may be provided on the inner side in the radial direction in the main body portion 21. Also, three notches for exposing a part of the second portion 32 of the three bus bars 30 may be provided on the outer side in the radial direction.

[0043] As shown in FIG. 6, the holder 20 may further include an outer wall portion 22 erected from the outer peripheral edge of the main body portion 21 toward the second axial direction Da2 and an inner wall portion 23 erected from the inner peripheral edge of the main body portion 21 toward the second axial direction Da2. A plurality of grooves may be recessed in the end surface of the main body portion 21 on the second axial direction Da2 side. These grooves, the outer wall portion 22, and the inner wall portion 23 can be used for temporarily positioning each divided core 11n when the core unit 11 is composed of a plurality of divided cores 11n.

[0044] [1-5. Second bus bar unit] The second bus bar unit 5 is a component that connects the three-phase coils 16 in a delta connection method (triangle connection method). As shown in FIG. 7, it has a holder 40 and a bus bar 50. The holder 40 is a non-conductive member, for example, made of resin. The bus bar 50 is a conductive member having a substrate portion 51 that forms a plate shape when viewed from the radial direction and a substantially arc shape when viewed from the axial direction. The substrate portion 51 is coated (embedded) in the holder 40. That is, the second bus bar unit 5 is provided such that the bus bar 50 is assembled with the resin holder 40 or is an insert molded product molded by the resin holder 40.

[0045] The second bus bar unit 5 is placed on the second axis direction Da2 side of the stator 3 with the holder 40 placed thereon in a state where one side (the first direction) in the plate thickness direction of the substrate portion 51 is along the second axis direction Da2. The second bus bar unit 5 of the present embodiment is placed on the second axis direction Da2 side of the stator 3 in a state where the first direction in the plate thickness direction of the substrate portion 51 coincides with the second axis direction Da2. That is, in the present embodiment, the second axis direction Da2 corresponds to the "first direction" described in the claims, and the first axis direction Da1 corresponds to the "second direction" described in the claims.

[0046] In the present embodiment, a plurality of bus bars 50 are provided to connect different two-phase coils 16 among the three-phase coils 16. On the second axis direction Da2 side of the stator 3 of the present embodiment, the starting lines Ws of the two U-phase coil groups 17u, the starting lines Ws of the two V-phase coil groups 17v, and the starting lines Ws of the two W-phase coil groups 17w are drawn out. Correspondingly, three bus bars 50, namely, a U-line bus bar 50u, a V-line bus bar 50v, and a W-line bus bar 50w, are provided in the second bus bar unit 5.

[0047] As shown in FIG. 3, the U-line bus bar 50u connects one starting line Ws of the two U-phase coil groups 17u and one starting line Ws of the two V-phase coil groups 17v. The V-line bus bar 50v connects the other starting line Ws of the two V-phase coil groups 17v and one starting line Ws of the two W-phase coil groups 17w. The W-line bus bar 50w connects the other starting line Ws of the two U-phase coil groups 17u and the other starting line Ws of the two W-phase coil groups 17w.

[0048] Also, in the present embodiment, each bus bar 50 is provided as a terminal electrically connected to an external power supply device (not shown). For this reason, each bus bar 50 further has a terminal portion 53 connected to the external power supply device.

[0049] The substrate portion 51 is, for example, substantially arc-shaped extending along the circumferential direction (that is, the direction orthogonal to the plate thickness direction). As shown in FIG. 8, the three substrate portions 51 are provided at the same axial position and are arranged so as not to overlap each other when viewed from the axial direction, that is, are provided on the same plane.

[0050] The starting wire Ws of each coil group 17 is joined to a part of the substrate portion 51. Hereinafter, the portion of the substrate portion 51 of each bus bar 50 to which the starting wire Ws is joined is referred to as a joining portion 52. As shown in FIG. 3, each of the U-phase bus bar 50u, the V-phase bus bar 50v, and the W-phase bus bar 50w may connect the starting wires Ws that are starting wires Ws of coil groups 17 of different phases and are drawn out from the common slot 15. Correspondingly, the joining portion 52 of each bus bar 50 may be provided so as to axially overlap with the slot 15 from which the starting wire Ws connected by the bus bar 50 is drawn out.

[0051] In the present embodiment, the starting wires Ws of each coil group 17 are drawn out from three slots 15 that are positioned every other one in the circumferential direction as described above. For this reason, each bus bar 50 is provided with one joining portion 52, and each of the three joining portions 52 is provided at equal intervals in the circumferential direction and spaced apart from each other so as to overlap with each of these three slots 15 as shown in FIG. 7. The three joining portions 52 are arranged, for example, to be located radially inward of the starting wire Ws in a state where the second bus bar unit 5 is placed on the stator 3. The radial positions of the three joining portions 52 are set to be substantially the same position. Note that FIG. 7 illustrates a state where the starting wire Ws is drawn out toward the second axial direction Da2 side.

[0052] The terminal portion 53 is formed in a flat plate shape that stands upright from the end portion in the extending direction of the substrate portion 51 toward the second axial direction Da2 side, for example. The three terminal portions 53 may be gathered at one location in the circumferential direction and arranged to be spaced apart from each other as shown in FIG. 7, for example. In the present embodiment, the three terminal portions 53 are gathered between the joining portion 52 of the U-phase bus bar 50u and the joining portion 52 of the V-phase bus bar 50v.

[0053] The substrate portion 51 of the U-line bus bar 50u, where the joint portion 52 is located on the second circumferential direction Dc2 side of the gathering location of the three terminal portions 53, extends so as to coincide with the circumferential direction, and the terminal portion 53 is continuously provided at the end on the first circumferential direction Dc1 side thereof. Further, the substrate portion 51 of the V-line bus bar 50v, where the joint portion 52 is located on the first circumferential direction Dc1 side of the gathering location of the three terminal portions 53, extends so as to coincide with the circumferential direction, and the terminal portion 53 is continuously provided at the end on the second circumferential direction Dc2 side thereof.

[0054] On the other hand, the substrate portion 51 of the W-line bus bar 50w, where the joint portion 52 is located at a position relatively far from the gathering location of the three terminal portions 53, extends so as to coincide with the circumferential direction in the vicinity of the joint portion 52, but extends so as to be located radially outward as it goes toward the first circumferential direction Dc1 side (as it moves away from the joint portion 52 and approaches the terminal portion 53). The substrate portion 51 of the W-line bus bar 50w is arranged radially outside the substrate portion 51 of the U-line bus bar 50u so as not to interfere with the substrate portion 51 of the U-line bus bar 50u on the first circumferential direction Dc1 side thereof. Specifically, the substrate portion 51 of the W-line bus bar 50w is arranged side by side with the substrate portion 51 of the U-line bus bar 50u in the radial direction with the starting line Ws connected to the U-line bus bar 50u interposed therebetween. The terminal portion 53 is continuously provided at the end on the first circumferential direction Dc1 side of the substrate portion 51 of the W-line bus bar 50w.

[0055] By arranging the respective substrate portions 51 of the U-line bus bar 50u, the V-line bus bar 50v, and the W-line bus bar 50w as described above, it becomes possible to arrange these substrate portions 51 at the same axial position without overlapping them in the axial direction, in other words, on the same plane.

[0056] As described above, the holder 40 is a resin member that covers the substrate portion 51 of the bus bar 50 and is placed on the stator 3. The holder 40 of the present embodiment has a main body portion 41 and a convex portion 42.

[0057] The main body portion 41 is a portion for covering the substrate portion 51 of each bus bar 50, and for example, it has an annular shape (doughnut shape) when viewed from the axial direction and a flat plate shape when viewed from the radial direction. In the main body portion 41, as part of a configuration for reducing the man-hours related to the assembly of the second bus bar unit 5 to the stator 3 and the joining of the starting line Ws (conductive wire) to the bus bar 50, an exposed portion 44 that exposes only the joint portion 52 of the substrate portion 51 and a guide portion 43 that guides the starting line Ws joined to the joint portion 52 are provided.

[0058] In the present embodiment, as shown in FIG. 8, the guide portion 43 is provided as a through hole that penetrates the main body portion 41 in the axial direction. Hereinafter, the guide portion 43 is also referred to as the through hole 43. When the second bus bar unit 5 is placed on the stator 3, the starting line Ws is inserted into the through hole 43 from the first axial direction Da1 toward the second axial direction Da2. Therefore, it can be said that the guide portion 43 is a portion that guides the starting line Ws from the first axial direction Da1 toward the second axial direction Da2.

[0059] The through hole 43 is provided at a position that overlaps the starting line Ws in the axial direction, in other words, at a position that overlaps the slot 15 from which the starting line Ws is drawn out. In the present embodiment, since the starting line Ws is drawn out from three locations in the circumferential direction (three slots 15 located at intervals of one in the circumferential direction), three through holes 43 are provided. As described above, the joint portion 52 of each bus bar 50 is provided at a position that axially overlaps the common slot 15 from which the starting line Ws to which the bus bar 50 is connected is drawn out. Therefore, it can also be said that each of the three through holes 43 is provided at the same circumferential position as each of the joint portions 52 of the three bus bars 50.

[0060] The starting lines Ws of the coil groups 17 of different phases to which each bus bar 50 is connected are drawn out from the common slot 15, inserted into the common through hole 43 as shown in FIG. 7, and joined to the joint portion 52 of the bus bar 50. In other words, by drawing out the starting lines Ws of the coil groups 17 of different phases connected by each bus bar 50 from the common slot 15 so as to be adjacent in the circumferential direction, it becomes possible to draw out two starting lines Ws from the common (one) through hole 43.

[0061] Also, among the windings W forming each coil group 17, the portions drawn out toward the second axial direction Da2 side are all starting lines Ws that serve as fixed ends. As described above, since the starting line Ws has the property that the position of the starting line Ws hardly varies for each coil group 17, it is possible to insert the starting line Ws into the through hole 43 simply by placing the second bus bar unit 5 on the stator 3. Therefore, since there is no need for a process of adjusting the position of the starting line Ws or locking the starting line Ws somewhere, the man-hours related to the assembly of the second bus bar unit 5 to the stator 3 can be reduced. Also, it is possible to draw out the starting line Ws with high reproducibility to a position suitable for joining to the joint portion 52, that is, a position passing through the through hole 43.

[0062] The exposed portion 44 is a portion that exposes only the joint portion 52 of the substrate portion 51 covered by the main body portion 41, and is provided around the guide portion 43. That is, it can be said that the guide portion 43 is attached to the exposed portion 44. Three exposed portions 44 are provided corresponding to the number of guide portions 43.

[0063] The exposed portion 44 may be formed, for example, by cutting out a part of the main body portion 41. In the present embodiment, the exposed portion 44 is provided as a notch (cut out) obtained by cutting out (notching) a portion (a part of the main body portion 41) on the inner or outer side in the radial direction of the through hole 43 in the main body portion 41 from the second axial direction Da2 side. The joint portion 52 of the substrate portion 51 is exposed in the second axial direction Da2 by such an exposed portion 44. Hereinafter, the exposed portion 44 is also referred to as a notch 44.

[0064] In the present embodiment, as described above, since the joint portion 52 is arranged to be located more radially inward than the starting line Ws, the notch 44 is provided adjacent to the inner side in the radial direction of the through hole 43. The notch 44 may be provided, for example, so as to cut out the entire area of the portion of the main body portion 41 that is more radially inward than the through hole 43, as shown in FIGS. 7 and 8. Also, the notch 44 may be provided without cutting out this entire area so as to leave a portion of the main body portion 41 that is more radially inward than the joint portion 52.

[0065] The notch 44 may be provided to expose not only the surface of the joint portion 52 facing the second axial direction Da2 but also the side surface of the joint portion 52 facing the radial direction, as shown in FIGS. 7 and 8, or may be provided to expose only the surface of the joint portion 52 facing the second axial direction Da2. Note that the notch 44 may be provided so as to penetrate the main body portion 41 in the axial direction. In this case, there is no clear boundary between the through hole 43 and the notch 44, and the through hole 43 is expanded by the notch 44.

[0066] The start line Ws inserted into the through hole 43 is bent radially inward and guided into the space formed by the notch 44 (the space where the main body portion 41 is partially hollowed out). In this way, since the bending of the start line Ws to the exposed portion 44 is guided by the guiding portion 43, the guiding portion 43 can also be regarded as a portion that guides the bending of the start line Ws to the exposed portion 44. Further, since the start line Ws is bent radially inward instead of radially outward, leakage of electricity from the start line Ws to the housing 6 is prevented.

[0067] Thereafter, the start line Ws abuts against the joint portion 52 exposed in the second axial direction Da2 by the notch 44 from the second axial direction Da2 side. The start line Ws abutted against the joint portion 52 is joined to the joint portion 52 by spot welding in which the joint portion 52 and the start line Ws are pressed and melt-bonded from the second axial direction Da2 side, rather than by conventional manual soldering. Therefore, the man-hours related to the joining of the start line Ws to the bus bar 50 can be reduced.

[0068] The joint portion 52 pressed in the first axial direction Da1 during spot welding is supported by the substrate portion 51 covered on the main body portion 41 of the holder 40 placed on the stator 3. Therefore, it is possible to prevent the joint portion 52 from moving to the first axial direction Da1 side or the bus bar 50 from falling off during spot welding. Note that the portion of the main body portion 41 located on the first axial direction Da1 side of the notch 44 can also function to support the joint portion 52 from the first axial direction Da1 side during spot welding of the joint portion 52 and the start line Ws.

[0069] In other words, in the present embodiment, the substrate portion 51 is covered by the holder 40 placed on the stator 3, and the notch 44 (exposed portion 44) that exposes the joint portion 52 of the substrate portion 51 in the second axial direction Da2 is provided, so that the joint portion 52 and the start line Ws can be joined by spot welding instead of the conventional manual soldering. Further, the portion of the winding W of each coil group 17 that is joined to the joint portion 52 is the start line Ws where the variation in the lead-out position is less likely to occur, and since these start lines Ws are always drawn out from the through hole 43, the reproducibility of the position of the start line Ws on the side to be spot welded is improved. Therefore, when automating the joining process of the start line Ws and incorporating it into the manufacturing process of the motor 1, it is possible to suppress the handling process of the start line Ws from becoming complicated.

[0070] In the present embodiment, as shown in FIG. 7, the joint portion 52 of each bus bar 50 is provided at a position excluding both ends in the extending direction of the substantially arc-shaped substrate portion 51. Further, the notch 44 is provided so that only the joint portion 52 of the substrate portion 51 is exposed, and the portions adjacent to both sides of the joint portion 52 in the extending direction of the substrate portion 51 are not exposed from the main body portion 41. In other words, only the joint portion 52 of the substrate portion 51 is exposed in the second axial direction Da2, and the portions adjacent to both sides of the joint portion 52 are covered by the holder 40 without being exposed. Thereby, the holding force of the bus bar 50 during spot welding of the joint portion 52 and the start line Ws is increased, and disengagement is suppressed.

[0071] The convex portion 42 is a portion for covering (embedding) the portion on the first axial direction Da1 side of the terminal portion 53 of each bus bar 50. The convex portion 42 protrudes, for example, from the gathering portion of the three terminal portions 53 toward the second axial direction Da2 side in the circumferential direction of the main body portion 41.

[0072] [2. Function, Effect] (1) In the above-described second bus bar unit 5, an exposed portion 44 and a guide portion 43 are provided on a holder 40 that covers the substrate portion 51 of the bus bar 50. A conducting wire (starting wire Ws) joined to a joint portion 52 that is a part of the substrate portion 51 is guided by the guide portion 43 to be bent toward the exposed portion 44 and abuts against the joint portion 52 exposed by the exposed portion 44. As a result, the conducting wire can be joined to the joint portion 52 by spot welding instead of by conventional manual soldering, so that the man-hours related to the joining of the conducting wire can be reduced.

[0073] (2) Further, if the exposed portion 44 is formed by a part of the main body portion 41 of the holder 40 being cut out, the conducting wire can be arranged in the cut-out space, so that it is possible to prevent the conducting wire from contacting other components (for example, the end bell 7 arranged on the second axial direction Da2 side of the second bus bar unit 5).

[0074] (3) In the above-described second bus bar unit 5 and motor 1, the substrate portion 51 of the bus bar 50 is covered by the holder 40, and an exposed portion 44 that exposes only the joint portion 52 of the substrate portion 51 in the first direction (here, the second axial direction Da2) in the plate thickness direction of the substrate portion 51, and a guide portion 43 that guides a conducting wire (starting wire Ws) from the second direction (here, the first axial direction Da1) in the plate thickness direction toward the first direction are provided on the holder 40. As a result, the conducting wire guided from the second direction toward the first direction by the guide portion 43 can be abutted against the joint portion 52 exposed by the exposed portion 44 attached to the guide portion 43 from the first direction side, and the conducting wire and the joint portion 52 can be joined by spot welding. Therefore, the man-hours related to the joining of the conducting wire can be reduced compared to conventional manual soldering.

[0075] (4) If the substrate portions 51 of the plurality of bus bars 50 provided in the second bus bar unit 5 are arranged so as to be located on the same plane, the thickness in the axial direction of the main body portion 41, that is, the portion of the holder 40 of the second bus bar unit 5 that covers the substrate portion 51, can be made thinner. Thereby, the second bus bar unit 5 can be made thinner, and by extension, it can contribute to the miniaturization of the device (here, the motor 1) to which the second bus bar unit 5 is applied.

[0076] (5) If the joint portion 52 is provided at a position excluding both end portions in the extending direction of the substrate portion 51 and the portions adjacent to both sides of the joint portion 52 in the extending direction of the substrate portion 51 are covered by the holder 40 without being exposed, the joint portion 52 is in a state of being supported at both ends. Therefore, the holding force of the bus bar 50 during spot welding is increased, and the bus bar 50 is prevented from coming off, so that the connection of the conducting wire to the joint portion 52 can be performed more appropriately.

[0077] (6) In the motor 1 described above, the starting wires Ws of the windings W forming the respective coils 16 (respective coil groups 17) of the stator 3 are all drawn out from the second axial direction Da2 side. Further, in the second bus bar unit 5, the holder 40 is placed on the second axial direction Da2 side of the stator 3. The guide portion 43 is provided as a through hole that axially penetrates and through which the starting wires Ws of the respective coils 16 (respective coil groups 17) are inserted, and the exposed portion 44 is provided as a notch that exposes the joint portion 52 of the substrate portion 51 in the second axial direction Da2 inside the radial direction of the through hole 43.

[0078] With such a configuration, by simply placing the holder 40 on the stator 3 while passing the starting wire Ws through the through hole 43, the assembly of the second bus bar unit 5 to the stator 3 is completed, so that the assembly man-hours can be reduced. Further, among the windings W forming the respective coils 16 (respective coil groups 17), the portions joined to the bus bar 50 of the second bus bar unit 5 are the starting wires Ws in which variations in their positions are less likely to occur. Therefore, when the holder 40 is placed on the stator 3, these starting wires Ws can be easily passed through the through hole 43. Also in this regard, the assembly man-hours can be reduced.

[0079] Furthermore, the joint 52 of the substrate portion 51 covered by the holder 40 placed on the stator 3 is exposed in the second axial direction Da2 by the notch 44, so that the starting wire Ws inserted through the through hole 43 and the joint 52 can be joined by spot welding from the second axial direction Da2 side where the stator 3 does not exist. Therefore, the man-hours related to the wiring process of the starting wire Ws can be reduced compared to the conventional manual soldering. In addition, since the joining of the starting wire Ws can be performed by spot welding instead of soldering that requires manual work, the joining process of the starting wire Ws can be automated and incorporated into the manufacturing process of the motor 1.

[0080] (7) In the second bus bar unit 5 described above, the notch 44 is provided inside the radial direction of the through hole 43. Thereby, the starting wire Ws inserted through the through hole 43 can be folded inside the radial direction instead of the outside in the radial direction and brought into contact with the joint 52, so that leakage of electricity from the starting wire Ws to the housing 6 can be prevented.

[0081] (8) If the starting wires Ws of different two-phase coils 16 (coil groups 17) connected by each bus bar 50 of the second bus bar unit 5 are drawn from the same slot 15 so as to be adjacent in the circumferential direction, these starting wires Ws can be inserted into one through hole 43 together and joined to the joint 52 by spot welding together. Therefore, the assembly man-hours can be further reduced.

[0082] [3. Others] The configurations of the second bus bar unit 5 and the motor 1 described above are examples and are not limited to the described configurations. For example, the motor 1 may be configured such that the second bus bar unit 5, the stator 3, and the first bus bar unit 4 are arranged in this order from the first axial direction Da1 toward the second axial direction Da2. In this case, the "first direction" and the "predetermined axial direction" described in the claims are the first axial direction Da1, and the "second direction" described in the claims is the second axial direction Da2. Note that the motor 1 may not include the first bus bar unit 4.

[0083] The second bus bar unit 5 does not have to be an insert molded product in which a plurality of bus bars 50 are molded by a resin holder 40, and may be a structure in which a plurality of bus bars 50 are assembled (assembled) inside the holder 40 after the resin holder 40 is molded. Similarly, the first bus bar unit 4 does not have to be an insert molded product, and may be a structure in which a plurality of bus bars 30 are assembled (assembled) inside the holder 20 after the resin holder 20 is molded. Note that the end wire Wf may be joined to the bus bar 30 of the first bus bar unit 4 by soldering.

[0084] The winding W provided in the stator 3 does not have to form two adjacent coils 16 of the same phase, and may form, for example, a single coil 16, or may form four consecutive coils 16 of the same phase. That is, the number of windings W provided in the stator 3 is not limited to the six described above. The start wires Ws of the windings W forming coils 16 of different phases adjacent in the circumferential direction do not have to be drawn from the same slot 15. The number of coils 16 provided in the stator 3 does not have to be twelve.

[0085] The bus bar 50 of the second bus bar unit 5 does not have to be a terminal electrically connected to an external power supply device, and may be a mere bus bar (conductor) that electrically connects a terminal electrically connected to an external power supply device and each coil 16 (each coil group 17). In this case, each substrate portion 51 of the U-phase bus bar 50u, the V-phase bus bar 50v, and the W-phase bus bar 50w may extend only around the joint portion 52 so as not to overlap in the circumferential direction.

[0086] The substrate portion 51 as the "substrate portion" described in claim 1 of the claims only has to be substantially arc-shaped, and does not have to be plate-shaped. Further, the substrate portion 51 as the "substrate portion" described in claim 3 of the claims only has to be plate-shaped, and does not have to be substantially arc-shaped. The joint portion 52 may be provided at an end in the extending direction of the plate-shaped substrate portion 51.

[0087] The holder 40 of the second bus bar unit 5 only needs to be in a shape that can cover the substrate portion 51 and does not have to be an annular shape. The holder 40 of the second bus bar unit 5 may be, for example, an arc shape, a disk shape, a fan shape, or a rectangle, and the main body portion 41 of the holder 40 does not have to be plate-shaped when viewed from the radial direction.

[0088] The notch 44 provided in the holder 40 of the second bus bar unit 5 may be provided on the outer side in the radial direction of the through hole 43. The through hole 43 and the notch 44 do not have to be provided for all of the joint portions 52 of the three bus bars 50 provided in the second bus bar unit 5, and may be provided only for the joint portion 52 of one of the three bus bars 50. When the two starting lines Ws to which each bus bar 50 of the second bus bar unit 5 is connected are drawn out at relatively distant positions in the circumferential direction, through holes 43 and notches 44 for joining the respective starting lines Ws to the substrate portion 51 may be provided. That is, the through hole 43 does not have to be a hole for drawing out the two starting lines Ws together, and a plurality of through holes 43 and notches 44 may be provided for the substrate portion 51 of one bus bar 50.

[0089] The exposed portion 44 only needs to be a portion that exposes at least only the joint portion 52 of the substrate portion 51, and does not have to be a notch formed by cutting out the main body portion 41 from the first direction side (second axial direction Da2 side). The guide portion 43 does not have to be a through hole that penetrates the main body portion 41 in the axial direction. The guide portion 43 may be, for example, a notch formed by cutting out the main body portion 41 from the outer side in the radial direction so as to penetrate the main body portion 41 in the axial direction.

[0090] The bus bar unit in which the guide portion 43 and the exposed portion 44 are provided does not have to be the second bus bar unit 5 that connects different two-phase coils 16 (coil groups 17) among the three-phase coils 16 (coil groups 17), and may be the first bus bar unit 4 that connects the three-phase coils 16 (each coil group 17) for each phase. The end wire Wf of the winding W may be joined to the bus bar unit. The bus bar unit only needs to be at least one to which a conducting wire is joined, and the conducting wire does not have to be the winding W provided in the stator 3.

[0091] When a plurality of bus bars are provided in the bus bar unit, the plate-like substrate portions of these bus bars may partially overlap in the plate thickness direction. Further, the bus bar unit may not include a plurality of bus bars.

Explanation of Signs

[0092] 1 Motor (brushless motor) 1s Shaft 2 Rotor 3 Stator 5 Second bus bar unit (bus bar unit) 15 Slot 16 Coil 16u U-phase coil (coil) 16v V-phase coil (coil) 16w W-phase coil (coil) 17 Coil group (coil) 17u U-phase coil group (coil) 17v V-phase coil group (coil) 17w W-phase coil group (coil) 40 Holder 41 Body part 43 Through hole (guide part) 44 Notch (exposed part) 50 Bus bar 50u U-line bus bar (bus bar) 50v V-line bus bar (bus bar) 50w W-line bus bar (bus bar) 51 Substrate part 52 Joint part (part of the substrate part) Da1 First axis direction (second direction) Da2 Second axis direction (first direction, predetermined axis direction) W Winding (conductive wire) Ws Starting wire (conductive wire)

Claims

1. A conductive bus bar having a plate-shaped substrate portion; a resin holder that covers the substrate portion, The holder includes: An exposure portion that exposes only a portion of the substrate portion in a first direction in a plate thickness direction of the substrate portion; a guide portion provided on the exposed portion and guiding the conductive wire joined to the portion from a second direction opposite to the first direction toward the first direction, The portion is provided at a position excluding both ends in an extension direction of the substrate portion, The portions of the substrate portion adjacent to both sides in the extending direction are covered by the holder without being exposed. The busbar unit according to the present invention is characterized in that

2. The bus bar is provided in plurality, The substrate portions of the plurality of bus bars are located on the same plane. The busbar unit according to claim 1 .

3. The present invention is applied to an inner rotor type brushless motor having an annular stator and a rotor located radially inward of the stator, The conductive wire is a starting wire of a winding that forms a coil of the stator, and is drawn out to a predetermined axial side in the axial direction of the stator, With the first direction aligned with the predetermined axial direction, The holder is placed on the predetermined axial side of the stator, The guide portion is a through hole penetrating in the axial direction and through which the starting wire is inserted, The exposed portion is a notch that exposes the part of the base plate portion in the predetermined axial direction on the inner side or the radially outer side of the through hole. The busbar unit according to claim 1 or 2, characterized in that

4. The notch is provided on the inner side of the through hole. The busbar unit according to claim 3 .

5. The busbar unit according to claim 3 ; the stator on which the busbar unit is mounted; The rotor rotates integrally with the shaft on the inner side of the stator. A brushless motor characterized by:

6. The stator is provided with a three-phase coil, the bus bar is a terminal that connects two different phase coils among the three-phase coils and is electrically connected to an external power supply device, and a plurality of bus bars are provided; the holder has the same number of through holes and notches as the number of the bus bars, The initial wires of the windings forming each of the coils of the two different phases connected to each of the bus bars are drawn out in the predetermined axial direction from the same slot, inserted into the common through hole, and joined to the portion of the bus bar.

6. The brushless motor according to claim 5 .

7. The present invention is applied to an inner rotor type brushless motor having an annular stator and a rotor located radially inward of the stator, A conductive bus bar having a plate-shaped substrate portion; a resin holder that covers the substrate portion, The holder includes: An exposure portion that exposes only a portion of the substrate portion in a first direction in a plate thickness direction of the substrate portion; a guide portion provided on the exposed portion and guiding the conductive wire joined to the portion from a second direction opposite to the first direction toward the first direction, The conductive wire is a starting wire of a winding that forms a coil of the stator, and is drawn out to a predetermined axial side in the axial direction of the stator, With the first direction aligned with the predetermined axial direction, The holder is placed on the predetermined axial side of the stator, The guide portion is a through hole penetrating in the axial direction and through which the starting wire is inserted, the exposed portion is a notch that exposes the part of the base plate portion in the predetermined axial direction on the inner side or the radially outer side of the through hole, The notch is provided on the inner side of the through hole. The busbar unit according to the present invention is characterized in that

8. The bus bar is provided in plurality, The substrate portions of the plurality of bus bars are located on the same plane. The busbar unit according to claim 7 .

9. A busbar unit according to claim 7, the stator on which the busbar unit is mounted; The rotor rotates integrally with the shaft on the inner side of the stator. A brushless motor characterized by:

10. The stator is provided with a three-phase coil, the bus bar is a terminal that connects two different phase coils among the three-phase coils and is electrically connected to an external power supply device, and a plurality of bus bars are provided; the holder has the same number of through holes and notches as the number of the bus bars, The initial wires of the windings forming each of the coils of the two different phases connected to each of the bus bars are drawn out in the predetermined axial direction from the same slot, inserted into the common through hole, and joined to the portion of the bus bar.

10. The brushless motor according to claim 9.

11. An inner rotor type brushless motor, A busbar unit; an annular stator on which the bus bar unit is mounted; a rotor located radially inward of the stator and rotating integrally with the shaft on the inner side of the stator, The busbar unit includes: A conductive bus bar having a plate-shaped substrate portion; a resin holder that covers the substrate portion, The holder includes: An exposure portion that exposes only a portion of the substrate portion in a first direction in a plate thickness direction of the substrate portion; a guide portion provided on the exposed portion and guiding the conductive wire joined to the portion from a second direction opposite to the first direction toward the first direction, The conductive wire is a starting wire of a winding that forms a coil of the stator, and is drawn out to a predetermined axial side in the axial direction of the stator, With the first direction aligned with the predetermined axial direction, The holder is placed on the predetermined axial side of the stator, The guide portion is a through hole penetrating in the axial direction and through which the starting wire is inserted, the exposed portion is a notch that exposes the part of the base plate portion in the predetermined axial direction on the inner side or the radially outer side of the through hole, The stator is provided with a three-phase coil, the bus bar is a terminal that connects two different phase coils among the three-phase coils and is electrically connected to an external power supply device, and a plurality of bus bars are provided; the holder has the same number of through holes and notches as the number of the bus bars, The initial wires of the windings forming each of the coils of the two different phases connected to each of the bus bars are drawn out in the predetermined axial direction from the same slot, inserted into the common through hole, and joined to the portion of the bus bar. A brushless motor characterized by:

12. The substrate portions of the plurality of bus bars are located on the same plane.

12. The brushless motor according to claim 11 .

Images